The official app does not have a function that enables temperature-dependent control. myStrom, however, has an open API that is supported by various systems. I use myStrom together with Home Assistant, which runs on a Raspberry Pie. In this combination, everything is theoretically possible because you can access the temperature sensors of myStrom and control the relay. However, I recommend using a different temperature sensor, as the sensor in the relay is not very accurate due to the self-heating of the myStrom adapter.